The prior art shows a device for the detection and indication of the heart action potential of a patient. The device includes a box-shaped housing equipped with three electrodes arranged on its bottom side. This apparatus is intended to be placed onto the chest of a patient in such a way that the electrodes make contact with the patient's skin. On the side of the housing opposite the side equipped with the electrodes is the screen of a cathode ray tube on which the changes in the reading of the body potential can be observed.
Such prior art devices are described in U.S. Pat. No. 3 858 576 of Dehnert et al.
These prior art devices have the disadvantage that, during use, the apparatus must be held in place by hand. Consequently, it is primarily suitable only for short, quick diagnosing of a patient. Furthermore, such instruments are adapted only for the reading of ECG potentials.
It is frequently necessary, especially during the transport of a patient, to continuously monitor the changes in his action potentials. This includes monitoring of not only heart action potentials, but also brain action potentials and muscle action potentials.